1. Field of the Invention
The present invention relates to a method for suppressing vibration generated during machining in a machine tool for performing machining while rotating a tool or a work, and a vibration suppressing device capable of executing this method.
2. Description of the Related Art
As for a vibration suppressing method of a machine tool, for example, a method disclosed in Japanese Unexamined Patent Publication No. 2003-340627 is conventionally known. According to this vibration suppressing method, in order to suppress regenerative type chatter vibration as self-excited vibration causing a low finishing workpiece surface roughness, a characteristic frequency of a system generating chatter vibration is obtained, e.g., a tool, a work, or the like, multiplying the characteristic frequency with 60, and dividing the multiplied value by the number of the tool flutes and a predetermined integer to be defined as a stable rotation speed. Then, by performing machining at this stable rotation speed, chatter vibration generated during machining is suppressed. In addition, the characteristic frequency is acquired by subjecting the tool or the work to impulse excitation.
Further, a vibration suppressing method disclosed in Japanese Translation of PCT No. 2001-517557 is also known. According to this vibration suppressing method, a chatter frequency of a system generating chatter vibration during machining is obtained, multiplying the chatter frequency with 60, and dividing the multiplied value by the number of the tool flutes and a predetermined integer to be defined as a stable rotation speed. By performing machining at this stable rotation speed, chatter vibration is intended to be suppressed. In addition, as for the chatter frequency during machining, a sound sensor is provided near the tool or the work, and the chatter frequency is acquired based on a vibration frequency detected by the sound sensor during rotation.